Rockwell Automation 1753-DNSI DeviceNet Safety Scanner for GuardPLC Controllers - Manual (Page 12)

Publication 1753-UM002A-EN-P - July 2005
1-2 Before You Begin
• HSP (High-speed Safety Protocol) Signature – This is a
read-only value that represents the data exchanged between the
GuardPLC controller and the safety scanner. The HSP Signature
is calculated based on the Scanner Configuration Signature and
changes only when the data exchanged by the controller and
the safety scanner changes. The HSP Signature is sent to the
controller configuration software and helps ensure the integrity
of the data.
• Controller ID (SRS) – A unique identifier for every GuardPLC
controller and GuardPLC Ethernet Distributed I/O module in a
system, the Controller ID must be a unique number from 1 to
65,535. The default is 60000.
• Safety-Lock – The safety scanner and DeviceNet safety I/O
modules must be Safety-Locked to prevent their configurations
from being unintentionally modified. Safety-Lock all DeviceNet
Safety devices by running the Safety Device Verification Wizard
in RSNetWorx for DeviceNet before placing the safety
application into service.
• Password protection – The configuration of the safety scanner
can be protected by the use of an optional password. If you set
a password in a safety device, the download, Safety-Reset,
Safety-Lock and Safety-Unlock operations will require a
password.
DeviceNet Safety Scanner
Communications The 1753-DNSI provides DeviceNet access for GuardPLC 1600 and
GuardPLC 1800 controllers. These GuardPLC controllers support
communications via High-Speed Safety Protocol (HSP). The
1753-DNSI reads and writes data from DeviceNet nodes and
exchanges this aggregate data with the GuardPLC controller via HSP.
The 1753-DNSI scanner communicates with DeviceNet devices over
the network to:
• read inputs from a device
• write outputs to a device
• monitor device status
How the 1753-DNSI Communicates
For standard data, the safety scanner communicates with a device
via strobe, poll, change of state, and/or cyclic messages. It uses these
messages to solicit data from or deliver data to each device in its
scanlist.